Remove FileDescriptor reference counting usage.

openJdk uses reference counting for closing FileDescriptor
instances. pre-openJdk code assumes that the creator
of FileDescriptor instance is responsible for its removal.
In pre-openJdk libcore, streams created by File(Input|
Output)Stream(FileDescriptor) will not close
received FileDescriptor.

This change reverts the code to the pre-openJdk behavior. We
found that there's code in framework (and possible some
third-party apps) that assumes pre-openJdk behavior.

Bug: 26408757
Change-Id: Idfd289f77417ac0e014bfd8bb29ecfaeec6fc5ae
4 files changed